{
  "abstract": "We investigate the evolution of Ly$α$ visibility and the physical properties of Ly$α$ emitters (LAEs) across the five CANDELS fields using publicly available JWST/NIRSpec PRISM spectroscopy. Our catalog comprises 3446 spectroscopically confirmed sources at 4 $\\leq $ z < 14.2, including 3361 star-forming galaxies (SFGs), of which 539 are robust (S/N > 3) LAEs. We measure the fraction of LAEs with EW$_0$ > 25A (X$_{\\mathrm{Lyα}}$) and trace its redshift evolution in two UV luminosity bins, namely -20.25 < M$_{\\mathrm{UV}}$ < -18.75 and -21.75 < M$_{\\mathrm{UV}}$ < -20.25. Within the fainter-UV range, X$_{\\mathrm{Lyα}}$ increases from z = 5 to z = 6 at 3$σ$ significance and subsequently declines toward higher redshifts with a significant monotonic trend at z > 6. We also investigate the physical properties of both LAEs and the full SFG population. We find that the stellar mass, UV slope $β$, stellar reddening, SFR, metallicity, sSFR, and burstiness of LAEs remain approximately stable with redshift. The only exception is the mass-weighted age which decreases with increased redshift. Conversely, the properties of the full SFG population evolve significantly, progressively approaching the region of galaxy-property space occupied by LAEs as redshift increases. This suggests that galaxy evolution may enhance the intrinsic production and escape of Ly$α$ photons toward earlier epochs. We argue that this effect should be accounted when inferring the evolution of the neutral hydrogen content of the IGM from the observed visibility of Ly$α$ emission. To this end, we employ a physically motivated framework based on the Attenuation-Free Model, jointly accounting for galaxy evolution and IGM attenuation. Our observations favor reionization histories that proceed gradually over scenarios characterized by a rapid increase in the cosmic neutral hydrogen fraction.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.00199",
  "author_total": 38,
  "authors": [
    {
      "name": "L. Napolitano"
    },
    {
      "name": "L. Pentericci"
    },
    {
      "name": "A. Ferrara"
    },
    {
      "name": "M. Llerena"
    },
    {
      "name": "M. Dickinson"
    },
    {
      "name": "A. Calabrò"
    },
    {
      "name": "S. L. Finkelstein"
    },
    {
      "name": "R. Begley"
    },
    {
      "name": "P. Arrabal Haro"
    },
    {
      "name": "A. Arroyo-Polonio"
    },
    {
      "name": "B. E. Backhaus"
    },
    {
      "name": "D. Bevacqua"
    },
    {
      "name": "A. Bhagwat"
    },
    {
      "name": "M. Bischetti"
    },
    {
      "name": "M. Castellano"
    },
    {
      "name": "S. -J. Chang"
    },
    {
      "name": "E. R. Cueto"
    },
    {
      "name": "V. D'Odorico"
    },
    {
      "name": "C. T. Donnan"
    },
    {
      "name": "M. Galbiati"
    },
    {
      "name": "G. Gandolfi"
    },
    {
      "name": "M. Giavalisco"
    },
    {
      "name": "M. Hirschmann"
    },
    {
      "name": "J. Kartaltepe"
    },
    {
      "name": "A. M. Koekemoer"
    },
    {
      "name": "K. K. Knudsen"
    },
    {
      "name": "R. A. Lucas"
    },
    {
      "name": "S. Mascia"
    },
    {
      "name": "L. Paquereau"
    },
    {
      "name": "B. Pérez-D\\'ıaz"
    },
    {
      "name": "C. Piscitelli"
    },
    {
      "name": "R. Rana"
    },
    {
      "name": "P. Santini"
    },
    {
      "name": "A. J. Taylor"
    },
    {
      "name": "E. Taylor"
    },
    {
      "name": "R. Tripodi"
    },
    {
      "name": "S. M. Wilkins"
    },
    {
      "name": "L. Y. A. Yung"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2474mg2fqdqf6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.00199",
  "fulltext_url": null,
  "id": "2474mg2fqdqf6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.00199",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7206216513",
  "pdf_url": "https://arxiv.org/pdf/2609.00199",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2474mg2fqdqf6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2609.00199",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.00199"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The gradual decline of Ly$α$ visibility in the CANDELS fields: evidence for the combined effects of galaxy evolution and reionization",
  "title_text": "The gradual decline of Lyα visibility in the CANDELS fields: evidence for the combined effects of galaxy evolution and reionization",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/2474mg2fqdqf6",
  "venue": "arXiv",
  "versions": []
}